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Synthesis and Thermal Behavior of New Precursors for B-C-N Ceramics

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Journal of Materials Science & Technology 2010年第3期26卷 228-233页

作者： shaohua dong Weijian Han Yongming Luo Tong Zhao Caihong Xu Institute of Chemistry Chinese Academy of Sciences Beijing 100190China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Three new borazine derivatives,2,4,6-tri（allylamino）borazine （CH 2 =CHCH 2 NHBNH） 3 （1）,2,4,6-tri（3ethynylanilino）borazine （CH≡CC 6 H 4 NHBNH） 3 （2）,and 2,4,6-tri（4-propargyl oxyanilino）borazine （CH≡ CCH 2 OC 6 H 4 NHBNH） 3 （3） were synthesized by reaction of 2,4,6-trichloro-borazine Cl 3 B 3 N 3 H 3 （TCB） with corresponding primary amines,*** thermal behavior was studied by differential scanning calorimetry （DSC） and thermogravimetric analysis （TGA）.These molecules were easily crosslinked via thermal polymerization of reactive ethynyl or vinyl *** pyrolytic residues of borazines were investigated by X-ray photoelectron spectroscopy （XPS）,powder X-ray diffraction （XRD）,and scanning electron microscopy （SEM）.The analytic results indicated that B-C-N ceramics were formed upon pyrolysis of the borazines under an inert atmosphere.

关键词： Precursors Thermal properties B-C-N ceramic

Metallogenic controls on the granite-related W–Sn deposits in the Hunan–Jiangxi region, China: evidence from zircon trace element geochemistry

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Acta Geochimica 2019年第4期38卷 530-540页

作者： Yuannan Feng Tingguang Lan Lichuan Pan Tingting Liu shaohua dong State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China The Fifth Geology Company of Hebei Geology and Mineral Bureau Tangshan 063000China

The Nanling Range in South China is well known for its rich granite-related W–Sn *** elucidate the controls of different granite-related W–Sn metallogenesis in the region,we chose five representative orerelated granites(Yanbei,Mikengshan,Tieshanlong,Qianlishan,and Yaogangxian intrusions)in the Hunan–Jiangxi region,and studied their magmatic zircon ages and trace element *** new zircon data showed the differences in ages,temperatures and oxygen fugacity of the ore-forming *** U–Pb ages of the Yanbei and Mikengshan intrusions are characterized by 142.4±2.4 and 143.0±2.3 Ma,respectively,whereas the Tieshanlong and Qianlishan intrusions are 159.5±2.3and 153.2±3.3 Ma,*** Sn-related intrusions were younger than the W-related *** Tiin-zircon thermometry showed that there was no systematic difference between the Sn-related Yanbei(680–744℃)and Mikengshan(697–763℃)intrusions and the W-related Tieshanlong(730–800℃),Qianlishan(690–755℃)and Yaogangxian(686–751℃)***,the zircon Ce^4+/Ce^3+ratios of the Yanbei(averaged at 18.3)and Mikengshan(averaged at 18.8)intrusions are lower than those of the Tieshanlong(averaged at 36.9),Qianlishan(averaged at 38.4)and Yaogangxian(averaged at 37)intrusions,indicating that the Sn-related granitic magmas might have lower oxygen fugacities than those of the *** can be explained by that,in more reduced magmas,Sn is more soluble than W and thus is more enriched in the residual melt to form Sn *** difference in source materials between the Sn-related and the W-related granites seems to have contributed to the different redox conditions of the melts.

关键词： W–Sn deposits South China Zircon trace element chemistry Ti-in-zircon thermometry Oxygen fugacity

Zircon U-Pb Ages and Sr-Nd-Hf Isotopic Characteristics of the Huichizi Granitic Complex in the North Qinling Orogenic Belt and Their Geological Significance

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Journal of Earth Science 2018年第3期29卷 492-507页

作者： Youwei Chen Ruizhong Hu Xianwu Bi shaohua dong Yue Xu Ting Zhou State Key Laboratory of Ore Deposit Geochemistry Chinese Academy of Sciences

The Huichizi granite complex is the largest Paleozoic 1-type intrusion located in the North Qinling orogenic belt （NQB）. In this study, we present systematic geochemical element data, zircon U-Pb ages, Ln-Hf isotopic data, and Sr-Nd isotopic data for the Huichizi granites. In terms of mineral and chemical compositions, these granites are biotite monzonitic and alkali-feldspar granites, both of which are characterized by high SiO2 and total alkali contents and low MgO, TiO2, and TFeO contents. These granites are weakly peraluminous （A/CNK values are 1-1.06 for biotite mon- zonitic granites and 1.04-1.09 for alkali-feldspar granites） and possess the geochemical characteristics of adakitic rocks, e.g., high Sr contents （319 ppm-633 ppm）, Sr/Y ratios （18.5-174）, and （La/Yb）N ratios （17.6-57） and low MgO （0.04 wt.%-0.83 wt.%）, Y （3.0 ppm-17.2 ppm）, and heavy rare-earth element （HREE） contents. This indicates that these rocks were most likely derived from the partial melting of a thickened lower crust. In situ zircon U-Pb dating of these granites yields Early Caledonian ages （437 Ma for biotite monzonitic granites and 424 Ma for alkali-feldspar granites）, indicating that the Huichizi granitic complex is the product of multi-periodic magmatism. The positive but varying zircon tHe（t） values （＋0.6 to ＋8.5） suggest that this thickened lower crust was mainly juvenile, i.e., accreted from depleted mantle during the Neo-Mesoproterozoic Period, but involved the ancient recycled crust. Biotite monzonitic granites formed during crust thickening at the extrusion stage, whereas the alkali granites formed during crust thickening at the extension stage （post extrusion）. The Huichizi granite complex witnessed the process of extrusion to extension because of the collision between the NCB and the Qinling microcontinent in the Caledonian.

关键词： U-Pb age Sr-Nd-Hf isotope Huichizi granitic complex adakitic granite North Qinling orogen.

Editorial: special topic on computation-assisted materials screening and design

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Science China Materials 2024年

作者： shaohua dong Jinlan Wang Chenghua Sun Science China Press School of Physics Southeast University Department of Chemistry and Biotechnology Swinburne University of Technology

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A Pipeline Fracture Model of Hydrogen-induced Cracking

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Petroleum Science 2006年第1期3卷 72-84页

作者： dong shaohua Fan Fei Gu Zhiyu Lv Yingmin Beijing Huayou Natural Gas Co. Ltd. PetroChina Beijing 100101 China Facalty of Mechanical and Electronic Engineering China University of Petroleum Beijing 102249 China

The relationship between hydrogen concentration and crack tip stress, strain field, hydrogen diffusion and internal pressure respectively in the crack tip process zone was investigated, and the length of the crack tip process zone of hydrogen-induced cracking （HIC） was determined. Based on the mechanism of fracture of micro-crack nucleation, a dislocation model was presented for the fracture criteria of HIC. The influence factors of pipeline tube fracture ductile KISCC in the presence of hydrogen was analyzed, and the critical pressure bearing capability of a pipeline with hydrogeninduced cracking and the critical J-integrity （JISCC） were calculated, which is very important for pipeline safety.

关键词： Pipeline HIC fracture model pressure bearing capability J-integrity

Transmissive reconfigurable metasurface enabling independent control of active and passive modules through weak coupling

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Photonics Research 2024年第7期12卷 1449-1456页

作者： KUN XUE HENG WEI CILEI ZHANG YONGHAO ZHANG HAOLIANG SUN shaohua dong Peng Cheng Laboratory Shenzhen 518055China Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore State Key Laboratory of Radio Frequency Heterogeneous Integration College of Electronics and Information EngineeringShenzhen UniversityShenzhen 518060China

Metasurfaces have demonstrated rich electromagnetic control capabilities and degrees of freedom in past years. As is well known, for passive metasurfaces, their functionalities cannot be further expanded accordingly once prototypes are established. Therefore, reconfigurable metasurfaces, utilizing active devices to replace geometric changes in passive structures, have received widespread attention, especially with the development of wireless communication recently. In reconfigurable metasurfaces, artificial meta-atoms are composed of active devices and passive structures combined together. However, these two modules are usually utilized as a whole due to the tight coupling of the active devices and the passive structures, which results in passive structures not receiving sufficient attention and being utilized as independent degrees of freedom. In this article, we propose the concept of weakly coupled reconfigurable metasurfaces in transmissive systems, enabling independent control of active and passive modules through weak coupling. As the proof of concept, a simple weakly coupled system is proposed, which can realize the transmission wavefront engineering through the geometric changes of meta-structures in passive mode, while achieving switching between transmission and reflection states in active mode, respectively. Our exploration lies in making use of the physical structure, which is easily neglected in traditional reconfigurable metasurface design, emphasizing the collaborative work of active and passive modules, exploring more available variables within the same aperture, and providing a potential solution for balancing functionality and resource consumption in practical applications.

关键词： modules coupling weakly

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基于磁流体的光纤传感器件的研究

基于磁流体的光纤传感器件的研究

作者： shaohua dong 上海理工大学

学位级别：硕士

传统的光纤传感技术已经在过去几十年吸引了巨大的关注并在很多领域得到了极大的应用,这归功于其优良的抗干扰特性、小巧简洁、耐高温高压以及高灵敏度的特点。另一方面,磁流体具备其独特的光学性质,如可调折射率、可调透射性、磁致各... 详细信息

传统的光纤传感技术已经在过去几十年吸引了巨大的关注并在很多领域得到了极大的应用,这归功于其优良的抗干扰特性、小巧简洁、耐高温高压以及高灵敏度的特点。另一方面,磁流体具备其独特的光学性质,如可调折射率、可调透射性、磁致各向异性等等,它既具有固体磁性材料的磁性又具备液体的流动性特点,这样的特性可以让它很容易和一些光子器件结合,组成新型的光子器件,比如可以和光纤传感器结合,制备出性能优良的光纤磁场传感器。为了让大家大致先了解传统的光纤传感器的基本情况,本文首先举例说明了一个比较简洁的典型传统光纤传感器——基于单模-多模-单模(SMS)光纤结构的曲率探测器。文中我们分别对两种不同参数的探测器做了研究,这两种探测器多模光纤(MMF)部分的长度分别为26 mm和48 mm。实验显示MMF部分长为26 mm的这一个探测器,其透射光谱中干涉谷对应的波长对曲率变化相对比较敏感,我们用其设计了“波长漂移型”曲率探测器。在曲率范围0.60-1.55 m-1,该曲率探测器对曲率变化有着良好的线性响应,得到的灵敏度为-13.17 nm/m-1。对于MMF部分长为48 mm的这个探测器,干涉谷波长对光纤曲率变化不敏感,但是干涉谷处的光强度对曲率变化比较敏感,我们用其设计了“强度变化型”曲率探测器。该曲率探测器,在0.22-0.89 m-1曲率范围内的线性灵敏度约为24.64 dB/m-1。我们将磁流体作为磁敏感材料包裹在特定光纤结构的外围,制备出基于磁流体的光纤磁场传感器。本文提出了两种此种类型的光纤磁场传感器,一种是基于taper-like和lateral-offset光纤熔接技术的光纤磁场探测器,另一种是基于up-tapered熔接节点的光纤磁场探测器。在研究实验现象的过程中,我们主要观察干涉谷波长和磁场变化的对应关系,以及干涉谷波长或者是特定波长处的透射光强和磁场变化的对应关系,用这两种方法来研究探测器的磁场响应情况。对于基于taper-like和lateral-offset熔接技术的光纤磁场探测器,在磁场38-225 Oe和250-475 Oe范围内干涉谷波长与磁场强度呈很好的线性关系,波长漂移灵敏度分别为14.1 pm/Oe和26 pm/Oe。在1566.36 nm波长处,我们在250-475 Oe磁场范围获得了透射强度随磁场变化的灵敏度为-0.024 dB/Oe。对于基于up-tapered熔接节点的光纤磁场探测器,我们在0-160 Oe的磁场范围内,获得了干涉谷波长随磁场漂移的灵敏度为32.53 pm/Oe,而且在20-300 Oe磁场范围,我们还获得了关于干涉谷对应透射光强随磁场变化的灵敏度为-0.02121 dB/Oe。在以往磁流体光学领域的研究及应用中,学者主要集中在磁流体在磁场下的折射率变化、透射系数的变化和各向异性这些光学特性,而本文首次研究了外界磁场对磁流体宏观体积变化的影响,详细阐述了磁流体在磁场调制下的体积变化对应的潜在物理机制。为了验证我们的理论分析和推测,我们将磁流体和传统的空气腔光纤FP干涉仪结合,利用FP干涉仪对腔体宽度变化的高灵敏度响应特点,制造出了基于磁流体磁致体积变化的空气腔光纤FP干涉仪,这个探测器可以灵敏地检测出磁流体在磁场下体积的微小变化。并且利用这一特性,我们将此探测器应用于磁场探测领域。当探头和磁场夹角为45°时,探测器可获得最高灵敏度11.73pm/Oe。

关键词：磁流体曲率探测可调折射率磁致体积变化光纤磁场探测器

中国油气管道完整性管理20年回顾与发展建议

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油气储运 2020年第3期39卷 241-261页

作者：董绍华中国石油大学(北京)管道技术与安全研究中心

近年来,管道完整性管理逐渐成为全球管道行业预防事故发生、实现事前预控的重要手段。阐述了中国油气管道完整性管理20年发展历程,形成了"三个一"技术群,即一套技术体系、一套标准体系、一套系统支持平台,覆盖管道线路、管输场站、储气... 详细信息

近年来,管道完整性管理逐渐成为全球管道行业预防事故发生、实现事前预控的重要手段。阐述了中国油气管道完整性管理20年发展历程,形成了"三个一"技术群,即一套技术体系、一套标准体系、一套系统支持平台,覆盖管道线路、管输场站、储气库及系统平台等多个领域:在管道线路完整性方面,形成本体安全保障、风险评估与控制、输送介质安全保障、抢维修及应急保障等技术群;在场站完整性管理方面,形成站场工艺设施检测与评估、压缩机组诊断评估、定量风险评估、安全等级评估、设施完整性评价等技术群;在储气库方面,形成地下储气库风险控制、储气库建库及运行安全技术群;在完整性系统平台方面,形成基于业务多源数据的管道应急决策GIS系统,智能管网已在中俄东线初步建成。由此分析了中国管道完整性管理当前存在的问题及未来的发展趋势,提出中国管道完整性管理的发展目标是基于全生命周期智慧管网的完整性风险管控,而中国管道完整性技术发展的新方向则涵盖智能化数据采集、风险精准识别、系统自适应反馈、高精度完整性检测评价等.

关键词：油气管道完整性管理完整性技术智能化

湘中地区龙山金锑矿床酸性岩脉U-Pb年代学和Hf同位素特征及其地质意义

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岩石学报 2016年第11期32卷 3469-3488页

作者：陈佑纬毕献武付山岭董少花中国科学院地球化学研究所矿床地球化学国家重点实验室贵阳550081

本研究选择龙山金锑矿床外围出露的酸性岩脉(花岗斑岩脉、花岗闪长斑岩脉)开展系统的地球化学、锆石U-Pb年代学及Hf同位素研究,以查明湘中盆地内酸性岩脉的形成时代、源区特征及构造背景,并探讨了酸性岩脉与龙山金锑矿床的关系。锆石U-P... 详细信息

本研究选择龙山金锑矿床外围出露的酸性岩脉(花岗斑岩脉、花岗闪长斑岩脉)开展系统的地球化学、锆石U-Pb年代学及Hf同位素研究,以查明湘中盆地内酸性岩脉的形成时代、源区特征及构造背景,并探讨了酸性岩脉与龙山金锑矿床的关系。锆石U-Pb定年结果显示,龙山地区出露的5条酸性岩脉具有一致的结晶年龄,为220~217Ma,是印支晚期岩浆活动的产物。酸性岩脉的锆石Lu-Hf同位素组成特征也较为一致,176Hf/177Hf比值为0.282264~0.282536,εHf(t)=-13.4^-3.7,tDM2为2089~1482Ma。结合元素地球化学特征,表明龙山地区出露的酸性岩脉可能主要由深部的古-中元古代浅变质碎屑岩在碰撞后伸展背景下减压部分熔融形成。酸性岩脉的成岩年龄与龙山金锑矿印支晚期成矿年龄大体一致。结合前人的研究,我们认为印支晚期的岩浆活动可能是龙山金锑矿成矿的重要热源和流体来源之一。

关键词：龙山金锑矿床酸性岩脉锆石U—Pb年龄 Hf同位素湘中地区